RESUMEN
Acetylcholine regulates various cognitive functions through broad cholinergic innervation. However, specific cholinergic subpopulations, circuits and molecular mechanisms underlying recognition memory remain largely unknown. Here we show that Ngfr+ cholinergic neurons in the substantia innominate (SI)/nucleus basalis of Meynert (nBM)-medial prefrontal cortex (mPFC) circuit selectively underlies recency judgements. Loss of nerve growth factor receptor (Ngfr-/- mice) reduced the excitability of cholinergic neurons in the SI/nBM-mPFC circuit but not in the medial septum (MS)-hippocampus pathway, and impaired temporal order memory but not novel object and object location recognition. Expression of Ngfr in Ngfr-/- SI/nBM restored defected temporal order memory. Fiber photometry revealed that acetylcholine release in mPFC not only predicted object encounters but also mediated recency judgments of objects, and such acetylcholine release was absent in Ngfr-/- mPFC. Chemogenetic and optogenetic inhibition of SI/nBM projection to mPFC in ChAT-Cre mice diminished mPFC acetylcholine release and deteriorated temporal order recognition. Impaired cholinergic activity led to a depolarizing shift of GABAergic inputs to mPFC pyramidal neurons, due to disturbed KCC2-mediated chloride gradients. Finally, potentiation of acetylcholine signaling upregulated KCC2 levels, restored GABAergic driving force and rescued temporal order recognition deficits in Ngfr-/- mice. Thus, NGFR-dependent SI/nBM-mPFC cholinergic circuit underlies temporal order recognition memory.
Asunto(s)
Acetilcolina , Neuronas Colinérgicas , Corteza Prefrontal , Animales , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Neuronas Colinérgicas/metabolismo , Neuronas Colinérgicas/fisiología , Acetilcolina/metabolismo , Ratones , Masculino , Ratones Noqueados , Reconocimiento en Psicología/fisiología , Núcleo Basal de Meynert/metabolismo , Núcleo Basal de Meynert/fisiología , Ratones Endogámicos C57BL , Células Piramidales/metabolismo , Células Piramidales/fisiología , Hipocampo/metabolismo , Receptores de Factor de Crecimiento NerviosoRESUMEN
Antiretroviral drugs have made significant progress in treating HIV-1 and improving the quality of HIV-1-infected individuals. However, due to their limited permeability into the brain HIV-1 replication persists in brain reservoirs such as perivascular macrophages and microglia, which cause HIV-1-associated neurocognitive disorders. Therefore, it is highly desirable to find a novel therapy that can cross the blood-brain barrier (BBB) and target HIV-1 pathogenesis in brain reservoirs. A recently developed 2-amino-3-methylpentanoic acid [2-morpholin-4-yl-ethyl]-amide (LM11A-31), which is a p75 neutrotrophin receptor (p75NTR) modulator, can cross the BBB. In this study, we examined whether LM11A-31 treatment can suppress HIV-1 replication, oxidative stress, cytotoxicity, and inflammatory response in macrophages. Our results showed that LM11A-31 (100 nM) alone and/or in combination with positive control darunavir (5.5 µM) significantly suppresses viral replication and reduces cytotoxicity. Moreover, the HIV-1 suppression by LM11A-31 was comparable to the HIV-1 suppression by darunavir. Although p75NTR was upregulated in HIV-1-infected macrophages compared to uninfected macrophages, LM11A-31 did not significantly reduce the p75NTR expression in macrophages. Furthermore, our study illustrated that LM11A-31 alone and/or in combination with darunavir significantly suppress pro-inflammatory cytokines including IL-1ß, IL-8, IL-18, and TNF-α and chemokines MCP-1 in HIV-induced macrophages. The suppression of these cytokines and chemokines by LM11A-31 was comparable to darunavir. In contrast, LM11A-31 did not significantly alter oxidative stress, expression of antioxidant enzymes, or autophagy marker proteins in U1 macrophages. The results suggest that LM11A-31, which can cross the BBB, has therapeutic potential in suppressing HIV-1 and inflammatory response in brain reservoirs, especially in macrophages.
Asunto(s)
VIH-1 , Macrófagos , Morfolinas , Replicación Viral , VIH-1/efectos de los fármacos , Humanos , Replicación Viral/efectos de los fármacos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Macrófagos/virología , Morfolinas/farmacología , Estrés Oxidativo/efectos de los fármacos , Inflamación/tratamiento farmacológico , Inflamación/metabolismo , Darunavir/farmacología , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Receptores de Factor de Crecimiento Nervioso/metabolismo , Citocinas/metabolismo , Isoleucina/análogos & derivados , Proteínas del Tejido NerviosoRESUMEN
Neurotrophins and their receptors are distinctly expressed during brain development and play crucial roles in the formation, survival, and function of neurons in the nervous system. Among these molecules, brain-derived neurotrophic factor (BDNF) has garnered significant attention due to its involvement in regulating GABAergic system development and function. In this review, we summarize and compare the expression patterns and roles of neurotrophins and their receptors in both the developing and adult brains of rodents, macaques, and humans. Then, we focus on the implications of BDNF in the development and function of GABAergic neurons from the cortex and the striatum, as both the presence of BDNF single nucleotide polymorphisms and disruptions in BDNF levels alter the excitatory/inhibitory balance in the brain. This imbalance has different implications in the pathogenesis of neurodevelopmental diseases like autism spectrum disorder (ASD), Rett syndrome (RTT), and schizophrenia (SCZ). Altogether, evidence shows that neurotrophins, especially BDNF, are essential for the development, maintenance, and function of the brain, and disruptions in their expression or signaling are common mechanisms in the pathophysiology of brain diseases.
Asunto(s)
Factor Neurotrófico Derivado del Encéfalo , Neuronas GABAérgicas , Humanos , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Neuronas GABAérgicas/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Trastornos del Neurodesarrollo/metabolismo , Trastornos del Neurodesarrollo/genética , Factores de Crecimiento Nervioso/metabolismo , Factores de Crecimiento Nervioso/genética , Encéfalo/metabolismo , Encéfalo/crecimiento & desarrolloRESUMEN
Genetic variants in ABCA7, an Alzheimer's disease (AD)-associated gene, elevate AD risk, yet its functional relevance to the etiology is unclear. We generated a CRISPR-Cas9-mediated abca7 knockout zebrafish to explore ABCA7's role in AD. Single-cell transcriptomics in heterozygous abca7+/- knockout combined with Aß42 toxicity revealed that ABCA7 is crucial for neuropeptide Y (NPY), brain-derived neurotrophic factor (BDNF), and nerve growth factor receptor (NGFR) expressions, which are crucial for synaptic integrity, astroglial proliferation, and microglial prevalence. Impaired NPY induction decreased BDNF and synaptic density, which are rescuable with ectopic NPY. In induced pluripotent stem cell-derived human neurons exposed to Aß42, ABCA7-/- suppresses NPY. Clinical data showed reduced NPY in AD correlated with elevated Braak stages, genetic variants in NPY associated with AD, and epigenetic changes in NPY, NGFR, and BDNF promoters linked to ABCA7 variants. Therefore, ABCA7-dependent NPY signaling via BDNF-NGFR maintains synaptic integrity, implicating its impairment in increased AD risk through reduced brain resilience.
Asunto(s)
Enfermedad de Alzheimer , Factor Neurotrófico Derivado del Encéfalo , Neuropéptido Y , Transducción de Señal , Pez Cebra , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor Neurotrófico Derivado del Encéfalo/genética , Animales , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/patología , Neuropéptido Y/metabolismo , Neuropéptido Y/genética , Humanos , Sinapsis/metabolismo , Sinapsis/patología , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Receptores de Factor de Crecimiento Nervioso/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Neuronas/metabolismo , Neuronas/patología , Péptidos beta-Amiloides/metabolismo , Péptidos beta-Amiloides/genéticaRESUMEN
RESEARCH QUESTION: Theca interna cells (TICs) are an indispensable cell source for ovarian follicle development and steroidogenesis. Recent studies have identified theca stem cells (TSCs) in both humans and animals. Interestingly, TSCs express mesenchymal stem cell (MSC)-related markers and can differentiate into mesenchymal lineages. MSCs are promising for tissue engineering and regenerative medicine due to their self-renewal and differentiation abilities. Therefore, this study investigated the potential origin of TICs from MSCs. DESIGN: Whole ovaries from postmenopausal organ donors were obtained, and their cortex was cryopreserved prior to the isolation of stromal cells. These isolated cells were differentiated in vitro to TICs using cell media enriched with various growth factors and hormones. Immunocytochemistry, an enzyme-linked immunosorbent assay, flow cytometry, and reverse transcription-quantitative polymerase chain were employed at different timepoints. Data were analyzed using one-way ANOVA. RESULTS: Immunocytochemistry showed an increase in TIC markers from day 0 to day 8 and a significant rise in MSC-like markers on day 2. This corresponds with rising androstenedione levels from day 2 to day 13. Flow cytometry identified a decreasing MSC-like cell population from day 2 onwards. The CD13+ cell population and its gene expression increased significantly over time. NGFR and PDGFRA expression was induced on days 0 and 2, respectively, compared to day 13. CONCLUSIONS: This study offers insights into MSC-like cells as the potential origin of TICs. Differentiating TICs from these widely accessible MSCs holds potential significance for toxicity studies and investigating TIC-related disorders like polycystic ovary syndrome (PCOS).
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Diferenciación Celular , Células Tecales , Femenino , Células Tecales/metabolismo , Células Tecales/citología , Humanos , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/citología , Células Madre Multipotentes/citología , Células Madre Multipotentes/metabolismo , Células Cultivadas , Biomarcadores/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismo , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genéticaRESUMEN
Age-related conditions, such as sarcopenia, cause physical disabilities for an increasing section of society. At the neuromuscular junction, the postsynaptic-derived neurotrophic factors brain-derived neurotrophic factor (BDNF) and neurotrophin 4 (NT-4) have neuroprotective functions and contribute to the correct regulation of the exocytotic machinery. Similarly, presynaptic muscarinic signalling plays a fundamental modulatory function in this synapse. However, whether or not these signalling pathways are compromised in ageing neuromuscular system has not yet been analysed. The present study analyses, through Western blotting, the differences in expression and activation of the main key proteins of the BDNF/NT-4 and muscarinic pathways related to neurotransmission in young versus ageing Extensor digitorum longus (EDL) rat muscles. The main results show an imbalance in several sections of these pathways: (i) a change in the stoichiometry of BDNF/NT-4, (ii) an imbalance of Tropomyosin-related kinase B receptor (TrkB)-FL/TrkB-T1 and neurotrophic receptor p 75 (p75NTR), (iii) no changes in the cytosol/membrane distribution of phosphorylated downstream protein kinase C (PKC)ßI and PKCε, (iv) a reduction in the M2-subtype muscarinic receptor and P/Q-subtype voltage-gated calcium channel, (v) an imbalance of phosphorylated mammalian uncoordinated-18-1 (Munc18-1) (S313) and synaptosomal-associated protein 25 (SNAP-25) (S187), and (vi) normal levels of molecules related to the management of acetylcholine (Ach). Based on this descriptive analysis, we hypothesise that these pathways can be adjusted to ensure neurotransmission rather than undergoing negative alterations caused by ageing. However, further studies are needed to assess this hypothetical suggestion. Our results contribute to the understanding of some previously described neuromuscular functional age-related impairments. Strategies to promote these signalling pathways could improve the neuromuscular physiology and quality of life of older people.
Asunto(s)
Envejecimiento , Factor Neurotrófico Derivado del Encéfalo , Unión Neuromuscular , Receptor trkB , Transducción de Señal , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Animales , Unión Neuromuscular/metabolismo , Envejecimiento/metabolismo , Ratas , Receptor trkB/metabolismo , Factores de Crecimiento Nervioso/metabolismo , Masculino , Receptores Muscarínicos/metabolismo , Transmisión Sináptica , Receptores de Factor de Crecimiento Nervioso/metabolismo , Ratas WistarRESUMEN
BACKGROUND: Brain recovery mechanisms after injuries like aneurysmal subarachnoid hemorrhage (aSAH), ischemic stroke (IS), and traumatic brain injury (TBI) involve brain plasticity, synaptic regeneration, and neuroinflammation. We hypothesized that serum levels of the p75 neurotrophic receptor (p75NTR) and associated signaling proteins, as well as differentially expressed (DE) microRNAs, could predict recovery outcomes irrespective of injury type. METHODS: A prospective patient cohort with ischemic stroke (IS, n = 30), aneurysmal subarachnoid hemorrhage (aSAH, n = 31), and traumatic brain injury (TBI, n = 13) were evaluated (total n = 74). Serum samples were collected at two post-injury intervals (early: 1-3 days, late: 4-8 days), and outcomes were assessed after three months using the modified Rankin Scale (mRS), categorizing outcomes as favorable (mRS 0-3) or unfavorable (mRS 4-6). Six proteins were measured using ELISAs: p75NTR, NGF, sortilin, IL1ß, TNFα, and cyclophilin. DE microRNAs were identified using DESeq2, and their target genes were predicted. Serum molecules between patients with differing outcomes were compared using a Kolmogorov-Smirnov test, 2-tailed t-test and multivariate linear discriminant analysis (LDA). RESULTS: Favorable (n = 46) and unfavorable (n = 28) outcome cohorts were balanced with age and sex (p = 0.25 and 0.63). None of the studied proteins correlated with age. Combinatory LDA of the six protein biomarkers indicated strong prognostic value for favorable outcomes (OR 2.09; AUC = 70.3%, p = 0.0058). MicroRNA expression changes over time were identified in the aSAH, TBI, and IS groups (p < 0.05, FDR corrected). Twenty-three microRNAs were commonly DE across all brain injury groups when comparing favorable and unfavorable outcomes (p < 0.05). LDA of four microRNAs targeting the studied proteins showed high prognostic accuracy (OR 11.7; AUC = 94.1%, p = 0.016). CONCLUSIONS: The combined prognostic microRNA and protein biomarker models demonstrated accurate outcome prognostication across diverse injury types, implying the presence of a common recovery mechanism. DE microRNAs were found to target the studied molecules, suggesting a potential mechanistic role in recovery. Further investigation is warranted to study these molecules in prognostication, as well as therapeutic targets for enhancing recovery.
Asunto(s)
Biomarcadores , MicroARN Circulante , Plasticidad Neuronal , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Biomarcadores/sangre , MicroARN Circulante/sangre , Anciano , Plasticidad Neuronal/fisiología , Adulto , Hemorragia Subaracnoidea/sangre , Lesiones Traumáticas del Encéfalo/sangre , Lesiones Traumáticas del Encéfalo/diagnóstico , Estudios de Cohortes , Enfermedades Neuroinflamatorias/sangre , Accidente Cerebrovascular Isquémico/sangre , Receptores de Factor de Crecimiento Nervioso/sangre , Receptores de Factor de Crecimiento Nervioso/genética , Recuperación de la Función/fisiología , Pronóstico , Proteínas del Tejido Nervioso , Proteínas Adaptadoras del Transporte VesicularRESUMEN
Hippocampal area CA2 has garnered attention in recent times owing to its significant involvement in social memory and distinctive plasticity characteristics. Research has revealed that the CA2 region demonstrates a remarkable resistance to plasticity, particularly in the Schaffer Collateral (SC)-CA2 pathway. In this study we investigated the role of Nogo-A, a well-known axon growth inhibitor and more recently discovered plasticity regulator, in modulating plasticity within the CA2 region. The findings demonstrate that blocking Nogo-A in male rat hippocampal slices facilitates the establishment of both short-term and long-term plasticity in the SC-CA2 pathway, while having no impact on the Entorhinal Cortical (EC)-CA2 pathway. Additionally, the study reveals that inhibiting Nogo-A enables association between the SC and EC pathways. Mechanistically, we confirm that Nogo-A operates through its well-known co-receptor, p75 neurotrophin receptor (p75NTR), and its downstream signaling factor such as Rho-associated protein kinase (ROCK), as their inhibition also allows plasticity induction in the SC-CA2 pathway. Additionally, the induction of long-term depression (LTD) in both the EC and SC-CA2 pathways led to persistent LTD, which was not affected by Nogo-A inhibition. Our study demonstrates the involvement of Nogo-A mediated signaling mechanisms in limiting synaptic plasticity within the CA2 region.
Asunto(s)
Región CA2 Hipocampal , Plasticidad Neuronal , Proteínas Nogo , Sinapsis , Animales , Proteínas Nogo/metabolismo , Masculino , Plasticidad Neuronal/fisiología , Sinapsis/fisiología , Sinapsis/efectos de los fármacos , Sinapsis/metabolismo , Región CA2 Hipocampal/fisiología , Región CA2 Hipocampal/metabolismo , Región CA2 Hipocampal/efectos de los fármacos , Ratas Sprague-Dawley , Ratas , Quinasas Asociadas a rho/metabolismo , Quinasas Asociadas a rho/antagonistas & inhibidores , Corteza Entorrinal/fisiología , Corteza Entorrinal/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Vías Nerviosas/fisiología , Proteínas de la Mielina/metabolismo , Proteínas de la Mielina/genética , Proteínas del Tejido Nervioso , Receptores de Factores de CrecimientoRESUMEN
BACKGROUND AND AIMS: The goal of this study was to define basic constituents of the adult peripheral nervous system (PNS) using intact human nerve tissues. METHODS: We combined fluorescent and chromogenic immunostaining methods, myelin-selective fluorophores, and routine histological stains to identify common cellular and noncellular elements in aldehyde-fixed nerve tissue sections. We employed Schwann cell (SC)-specific markers, such as S100ß, NGFR, Sox10, and myelin protein zero (MPZ), together with axonal, extracellular matrix (collagen IV, laminin, fibronectin), and fibroblast markers to assess the SC's relationship to myelin sheaths, axons, other cell types, and the acellular environment. RESULTS: Whereas S100ß and Sox10 revealed mature SCs in the absence of other stains, discrimination between myelinating and non-myelinating (Remak) SCs required immunodetection of NGFR along with axonal and/or myelin markers. Surprisingly, our analysis of NGFR+ profiles uncovered the existence of at least 3 different novel populations of NGFR+/S100ß- cells, herein referred to as nonglial cells, residing in the stroma and perivascular areas of all nerve compartments. An important proportion of the nerve's cellular content, including circa 30% of endoneurial cells, consisted of heterogenous S100ß negative cells that were not associated with axons. Useful markers to identify the localization and diversity of nonglial cell types across different compartments were Thy1, CD34, SMA, and Glut1, a perineurial cell marker. INTERPRETATION: Our optimized methods revealed additional detailed information to update our understanding of the complexity and spatial orientation of PNS-resident cell types in humans.
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Nervios Periféricos , Subunidad beta de la Proteína de Unión al Calcio S100 , Humanos , Nervios Periféricos/citología , Nervios Periféricos/metabolismo , Subunidad beta de la Proteína de Unión al Calcio S100/análisis , Subunidad beta de la Proteína de Unión al Calcio S100/metabolismo , Células de Schwann/metabolismo , Receptores de Factor de Crecimiento Nervioso/análisis , Receptores de Factor de Crecimiento Nervioso/metabolismo , Masculino , Femenino , Factores de Transcripción SOXE/metabolismo , Factores de Transcripción SOXE/análisis , Adulto , Persona de Mediana Edad , Axones/metabolismo , Anciano , Vaina de Mielina/metabolismo , Proteínas del Tejido NerviosoRESUMEN
The p75NTR neurotrophin receptor has positive and negative roles regulating cell survival in the nervous system. Unambiguous interpretation of p75NTR function in vivo has been complicated, however, by residual expression of alternate forms of p75NTR protein in initial p75NTR knock-out mouse models. As rats are the preferred rodent for studying brain and behaviour, and to simplify interpretation of the knock-out phenotype, we report here the generation of a mutant rat devoid of the p75NTR protein. TALEN-mediated recombination in embryonic stem cells (ESCs) was used to flank exon 2 of p75NTR with Lox P sites and produce transgenic rats carrying either un-recombined floxed p75NTREx2-fl, or recombined, exon-2 deleted p75NTREx2-Δ alleles. Crossing p75NTREx2-fl rats with a Cre-deleter strain efficiently removed exon 2 in vivo. Excision of exon 2 causes a frameshift after p75NTR Gly23 and eliminated p75NTR protein expression. Rats lacking p75NTR were healthy, fertile, and histological analysis did not reveal significant changes in cellular density or overall structure in their brains. p75NTR function is therefore largely dispensable for normal development, growth and basal homeostasis in the rat. However, the availability of constitutive and conditional p75NTREx2-Δ rats provides new opportunities to investigate specific roles of p75NTR upon injury and during tissue repair.
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Ratas Transgénicas , Animales , Ratas , Receptores de Factor de Crecimiento Nervioso/genética , Receptores de Factor de Crecimiento Nervioso/metabolismo , Fertilidad/genética , Femenino , Encéfalo/metabolismo , Encéfalo/crecimiento & desarrollo , Masculino , Exones/genética , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Células Madre Embrionarias/metabolismo , Receptores de Factores de CrecimientoRESUMEN
Juvenile angiofibroma (JA) is a rare, sex-specific, and highly vascularized nasal tumor that almost exclusively affects male adolescents, but its etiology has been controversial. The G protein-coupled hormone receptor LHCGR [luteinizing hormone (LH)/choriogonadotropin (hCG) receptor] represents a promising new candidate for elucidating the underlying mechanisms of sex specificity, pubertal manifestation, and JA progression. We used highly sensitive RNAscope technology, together with immunohistochemistry, to investigate the cellular expression, localization, and distribution of LHCGR in tissue samples from JA patients. Our results provide evidence for LHCGR expression in subsets of cells throughout JA tissue sections, with the majority of LHCGR+ cells located in close vicinity to blood vessels, rendering them susceptible to endocrine LH/hCG signaling, but LHCGR+ cells were also detected in fibrocollagenous stroma. A majority of LHCGR+ cells located near the vascular lumen co-expressed the neural crest stem cell marker CD271. These results are intriguing as both LH and hCG are produced in a time- and sex-dependent manner, and are known to be capable of inducing cell proliferation and angiogenesis. Our results give rise to a new model that suggests endocrine mechanisms involving LHCGR and its ligands, together with autocrine and paracrine signaling, in JA vascularization and cell proliferation.
Asunto(s)
Angiofibroma , Receptores de HL , Humanos , Receptores de HL/metabolismo , Masculino , Angiofibroma/metabolismo , Angiofibroma/patología , Femenino , Adolescente , Neoplasias Nasales/metabolismo , Neoplasias Nasales/patología , Niño , Caracteres Sexuales , Proteínas del Tejido Nervioso , Receptores de Factor de Crecimiento NerviosoRESUMEN
BACKGROUND: Angiogenesis is crucial in neuroprotection of secondary thalamic injury after cortical infarction. The p75 neurotrophin receptor (p75NTR) plays a key role in activating angiogenesis. However, the effects of p75NTR on angiogenesis in the thalamus after cortical infarction are largely unknown. Herein we investigate whether p75NTR facilitates angiogenesis to attenuate secondary thalamic damage via activating hypoxia-inducible factor 1α (HIF-1α)/vascular endothelial growth factor (VEGF) pathway mediated by Von Hippel-Lindau (VHL) after distal middle cerebral artery occlusion (dMCAO). METHODS: The male rat model of dMCAO was established. The effects of p75NTR on the angiogenesis was evaluated using RNA-sequencing, immunohistochemistry, western blot, quantitative real-time polymerase chain reaction, magnetic resonance imaging, behavior tests, viral and pharmacological interventions. RESULTS: We found that the p75NTR and vessel density were decreased in ipsilateral thalamus after dMCAO. The p75NTR-VHL interaction was reduced, which promoted the ubiquitination degradation of HIF-1α and reduced VEGF expression after dMCAO. Notably, p75NTR overexpression restrained the ubiquitination degradation of HIF-1α by inhibiting VHL-HIF-1α interaction, further promoted angiogenesis, increased cerebral blood flow of ipsilateral thalamus and improved neurological function after dMCAO. CONCLUSION: For the first time, we highlighted that the enhancement of p75NTR-VHL interaction promoted angiogenesis in attenuating secondary thalamic damage after dMCAO.
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Infarto de la Arteria Cerebral Media , Neovascularización Fisiológica , Ratas Sprague-Dawley , Tálamo , Animales , Masculino , Ratas , Tálamo/metabolismo , Tálamo/patología , Infarto de la Arteria Cerebral Media/complicaciones , Infarto de la Arteria Cerebral Media/patología , Neovascularización Fisiológica/fisiología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Receptores de Factor de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Infarto Cerebral/patología , Angiogénesis , Proteínas del Tejido Nervioso , Receptores de Factores de CrecimientoRESUMEN
Binge alcohol consumption during adolescence can produce lasting deficits in learning and memory while also increasing the susceptibility to substance use disorders. The adolescent intermittent ethanol (AIE) rodent model mimics human adolescent binge drinking and has identified the nucleus basalis magnocellularis (NbM) as a key site of pathology. The NbM is a critical regulator of prefrontal cortical (PFC) cholinergic function and attention. The cholinergic phenotype is controlled pro/mature neurotrophin receptor activation. We sought to determine if p75NTR activity contributes to the loss of cholinergic phenotype in AIE by using a p75NTR modulator (LM11A-31) to inhibit prodegenerative signaling during ethanol exposure. Male and female rats underwent 5 g/kg ethanol (AIE) or water (CON) exposure following 2-day-on 2-day-off cycles from postnatal day 25-57. A subset of these groups also received a protective dose of LM11A-31 (50 mg/kg) during adolescence. Rats were trained on a sustained attention task (SAT) and behaviorally relevant acetylcholine (ACh) activity was recorded in the PFC with a fluorescent indicator (AChGRAB 3.0). AIE produced learning deficits on the SAT, which were spared with LM11A-31. In addition, PFC ACh activity was blunted by AIE, which LM11A-31 corrected. Investigation of NbM ChAT+ and TrkA+ neuronal expression found that AIE led to a reduction of ChAT+TrkA+ neurons, which again LM11A-31 protected. Taken together, these findings demonstrate the p75NTR activity during AIE treatment is a key regulator of cholinergic degeneration.
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Acetilcolina , Neuronas Colinérgicas , Etanol , Corteza Prefrontal , Animales , Femenino , Masculino , Ratas , Acetilcolina/metabolismo , Atrofia , Conducta Animal/efectos de los fármacos , Neuronas Colinérgicas/metabolismo , Neuronas Colinérgicas/efectos de los fármacos , Modelos Animales de Enfermedad , Etanol/toxicidad , Proteínas del Tejido Nervioso , Corteza Prefrontal/metabolismo , Corteza Prefrontal/efectos de los fármacos , Ratas Sprague-Dawley , Receptores de Factores de Crecimiento , Receptores de Factor de Crecimiento Nervioso/metabolismoRESUMEN
p75 neurotrophin receptor (p75NTR) signaling pathways substantially overlap with degenerative networks active in Alzheimer disease (AD). Modulation of p75NTR with the first-in-class small molecule LM11A-31 mitigates amyloid-induced and pathological tau-induced synaptic loss in preclinical models. Here we conducted a 26-week randomized, placebo-controlled, double-blinded phase 2a safety and exploratory endpoint trial of LM11A-31 in 242 participants with mild to moderate AD with three arms: placebo, 200 mg LM11A-31 and 400 mg LM11A-31, administered twice daily by oral capsules. This trial met its primary endpoint of safety and tolerability. Within the prespecified secondary and exploratory outcome domains (structural magnetic resonance imaging, fluorodeoxyglucose positron-emission tomography and cerebrospinal fluid biomarkers), significant drug-placebo differences were found, consistent with the hypothesis that LM11A-31 slows progression of pathophysiological features of AD; no significant effect of active treatment was observed on cognitive tests. Together, these results suggest that targeting p75NTR with LM11A-31 warrants further investigation in larger-scale clinical trials of longer duration. EU Clinical Trials registration: 2015-005263-16 ; ClinicalTrials.gov registration: NCT03069014 .
Asunto(s)
Enfermedad de Alzheimer , Tomografía de Emisión de Positrones , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Masculino , Femenino , Anciano , Método Doble Ciego , Anciano de 80 o más Años , Imagen por Resonancia Magnética , Receptor de Factor de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Persona de Mediana Edad , Biomarcadores/líquido cefalorraquídeo , Resultado del Tratamiento , Isoleucina/análogos & derivados , Morfolinas , Proteínas del Tejido NerviosoRESUMEN
Identifying marker combinations for robust prognostic validation in primary tumour compartments remains challenging. We aimed to assess the prognostic significance of CSC markers (ALDH1, CD44, p75NTR, BMI-1) and E-cadherin biomarkers in OSCC. We analysed 94 primary OSCC and 67 metastatic lymph node samples, including central and invasive tumour fronts (ITF), along with clinicopathological data. We observed an increase in ALDH1+/CD44+/BMI-1- tumour cells in metastatic lesions compared to primary tumours. Multivariate analysis highlighted that elevated p75NTR levels (at ITF) and reduced E-cadherin expression (at the tumour centre) independently predicted metastasis, whilst ALDH1high exhibited independent predictive lower survival at the ITF, surpassing the efficacy of traditional tumour staging. Then, specifically at the ITF, profiles characterized by CSChighE-cadherinlow (ALDH1highp75NTRhighE-cadherinlow) and CSCintermediateE-cadherinlow (ALDH1 or p75NTRhighE-cadherinlow) were significantly associated with worsened overall survival and increased likelihood of metastasis in OSCC patients. In summary, our study revealed diverse tumour cell profiles in OSCC tissues, with varying CSC and E-cadherin marker patterns across primary tumours and metastatic sites. Given the pivotal role of reduced survival rates as an indicator of unfavourable prognosis, the immunohistochemistry profile identified as CSChighE-cadherinlow at the ITF of primary tumours, emerges as a preferred prognostic marker closely linked to adverse outcomes in OSCC.
Asunto(s)
Familia de Aldehído Deshidrogenasa 1 , Biomarcadores de Tumor , Cadherinas , Carcinoma de Células Escamosas , Neoplasias de la Boca , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Familia de Aldehído Deshidrogenasa 1/metabolismo , Biomarcadores de Tumor/metabolismo , Cadherinas/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/mortalidad , Receptores de Hialuranos/metabolismo , Inmunohistoquímica , Metástasis Linfática , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/diagnóstico , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Proteínas del Tejido Nervioso/metabolismo , Complejo Represivo Polycomb 1/metabolismo , Complejo Represivo Polycomb 1/genética , Pronóstico , Receptores de Factor de Crecimiento Nervioso/metabolismo , Retinal-Deshidrogenasa/metabolismoRESUMEN
RNAs, such as noncoding RNA, microRNA, and recently mRNA, have been recognized as signal transduction molecules. CD271, also known as nerve growth factor receptor, has a critical role in cancer, although the precise mechanism is still unclear. Here, we show that CD271 mRNA, but not CD271 protein, facilitates spheroid cell proliferation. We established CD271-/- cells lacking both mRNA and protein of CD271, as well as CD271 protein knockout cells lacking only CD271 protein, from hypopharyngeal and oral squamous cell carcinoma lines. Sphere formation was reduced in CD271-/- cells but not in CD271 protein knockout cells. Mutated CD271 mRNA, which is not translated to a protein, promoted sphere formation. CD271 mRNA bound to hnRNPA2B1 protein at the 3'-UTR region, and the inhibition of this interaction reduced sphere formation. In surgical specimens, the CD271 mRNA/protein expression ratio was higher in the cancerous area than in the noncancerous area. These data suggest CD271 mRNA has dual functions, encompassing protein-coding and noncoding roles, with its noncoding RNA function being predominant in oral and head and neck squamous cell carcinoma.
Asunto(s)
Neoplasias de Cabeza y Cuello , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B , Neoplasias de la Boca , Proteínas del Tejido Nervioso , ARN Mensajero , Receptores de Factor de Crecimiento Nervioso , Carcinoma de Células Escamosas de Cabeza y Cuello , Femenino , Humanos , Masculino , Regiones no Traducidas 3' , Línea Celular Tumoral , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo A-B/genética , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Neoplasias de la Boca/metabolismo , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Receptores de Factor de Crecimiento Nervioso/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismoRESUMEN
Patients suffering from sepsis-induced acute lung injury (ALI) exhibit a high mortality rate, and their prognosis is closely associated with infiltration of neutrophils into the lungs. In this study, we found a significant elevation of CD64+ neutrophils, which highly expressed p75 neurotrophin receptor (p75NTR) in peripheral blood of mice and patients with sepsis-induced ALI. p75NTR+CD64+ neutrophils were also abundantly expressed in the lung of ALI mice induced by lipopolysaccharide. Conditional knock-out of the myeloid lineage's p75NTR gene improved the survival rates, attenuated lung tissue inflammation, reduced neutrophil infiltration and enhanced the phagocytic functions of CD64+ neutrophils. In vitro, p75NTR+CD64+ neutrophils exhibited an upregulation and compromised phagocytic activity in blood samples of ALI patients. Blocking p75NTR activity by soluble p75NTR extracellular domain peptide (p75ECD-Fc) boosted CD64+ neutrophils phagocytic activity and reduced inflammatory cytokine production via regulation of the NF-κB activity. The findings strongly indicate that p75NTR+CD64+ neutrophils are a novel pathogenic neutrophil subpopulation promoting sepsis-induced ALI.
Asunto(s)
Lesión Pulmonar Aguda , Ratones Endogámicos C57BL , Neutrófilos , Fagocitosis , Receptores de IgG , Receptores de Factor de Crecimiento Nervioso , Sepsis , Animales , Lesión Pulmonar Aguda/inmunología , Lesión Pulmonar Aguda/etiología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Sepsis/inmunología , Sepsis/complicaciones , Humanos , Receptores de IgG/metabolismo , Receptores de IgG/genética , Receptores de IgG/inmunología , Ratones , Masculino , Fagocitosis/inmunología , Receptores de Factor de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso/genética , Receptores de Factor de Crecimiento Nervioso/inmunología , Ratones Noqueados , Lipopolisacáridos , Citocinas/metabolismo , Citocinas/inmunología , Pulmón/inmunología , Pulmón/patología , Femenino , FN-kappa B/metabolismo , FN-kappa B/inmunología , Proteínas del Tejido NerviosoRESUMEN
Osteoarthritis (OA) is a painful, incurable disease affecting over 500 million people. Recent clinical trials of the nerve growth factor (NGF) inhibitors in OA patients have suggested adverse effects of NGF inhibition on joint structure. Here we report that nerve growth factor receptor (NGFR) is upregulated in skeletal cells during OA and plays an essential role in the remodeling and repair of osteoarthritic joints. Specifically, NGFR is expressed in osteochondral cells but not in skeletal progenitor cells and induced by TNFα to attenuate NF-κB activation, maintaining proper BMP-SMAD1 signaling and suppressing RANKL expression in mice. NGFR deficiency hyper-activates NF-κB in murine osteoarthritic joints, which impairs bone formation and enhances bone resorption as exemplified by a reduction in subchondral bone and osteophytes. In human OA cartilage, NGFR is also negatively associated with NF-κB activation. Together, this study suggests a role of NGFR in limiting inflammation for repair of diseased skeletal tissues.
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Cartílago Articular , Osteoartritis , Humanos , Ratones , Animales , Receptor de Factor de Crecimiento Nervioso , FN-kappa B , Factor de Crecimiento Nervioso/metabolismo , Receptores de Factor de Crecimiento Nervioso , Inflamación , Cartílago Articular/metabolismo , Articulaciones/metabolismoRESUMEN
The neurotrophin nerve growth factor (NGF) and its precursor proNGF are both bioactive and exert similar or opposite actions depending on the cell target and its milieu. The balance between NGF and proNGF is crucial for cell and tissue homeostasis and it is considered an indicator of pathological conditions. Proteolytical cleavage of proNGF to the mature form results in different fragments, whose function and/or bioactivity is still unclear. The present study was conducted to investigate the distribution of proNGF fragments derived from endogenous cleavage in brain and peripheral tissues of adult rats in the healthy condition and following inflammatory lipopolysaccharide (LPS) challenge. Different anti-proNGF antibodies were tested and the presence of short peptides corresponding to the prodomain sequence (pdNGFpep) was identified. Processing of proNGF was found to be tissue-specific and accumulation of pdNGFpeps was found in inflamed tissues, mainly in testis, intestine and heart, suggesting a possible correlation between organ functions and a response to insults and/or injury. The bioactivity of pdNGFpep was also demonstrated in vitro by using primary hippocampal neurons. Our study supports a biological function for the NGF precursor prodomain and indicates that short peptides from residues 1-60, differing from the 70-110 sequence, induce apoptosis, thereby opening the way for identification of new molecular targets to study pathological conditions.
Asunto(s)
Factor de Crecimiento Nervioso , Neuronas , Masculino , Ratas , Animales , Factor de Crecimiento Nervioso/metabolismo , Neuronas/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo , Encéfalo/metabolismo , Hipocampo/metabolismoRESUMEN
Specific subpopulations of neurons in nerve and sensory systems must be developed and maintained, and this is accomplished in significant part by neurotrophins (NTs) and the signaling receptors on which they act, called tyrosine protein kinase receptors (Trks). The neurotrophins-tyrosine protein kinase receptors (NTs/Trks) system is involved in sensory organ regulation, including the visual system. An NTs/Trks system alteration is associated with neurodegeneration related to aging and diseases, including retinal pathologies. An emergent model in the field of translational medicine, for instance, in aging study, is the annual killifish belonging to the Nothobranchius genus, thanks to its short lifespan. Members of this genus, such as Nothobranchius guentheri, and humans share a similar retinal stratigraphy. Nevertheless, according to the authors' knowledge, the occurrence and distribution of the NTs/Trks system in the retina of N. guentheri has never been investigated before. Therefore, the present study aimed to localize neurotrophin BDNF, NGF, and NT-3 and TrkA, TrkB, and TrkC receptors in the N. guentheri retina using the immunofluorescence method. The present investigation demonstrates, for the first time, the occurrence of the NTs/Trks system in N. guentheri retina and, consequently, the potential key role of these proteins in the biology and survival of the retinal cells.